A teenage waitress has revealed how a customer left a racist insult in the 'tip’ line of a receipt.

Toni Christina Jenkins had just finished serving a couple at the Red Lobster restaurant in Tennessee on Saturday afternoon, when she discovered the slur.

In the slip for the $45 dinner, one of the customers had written ‘none’ in the tip line, and the word ‘nigger’ beneath it.

Scroll down to see the receipt

Toni Christina Jenkins is waitressing at the Red Lobster seafood restaurant as she trains to be a nurse

Jenkins, who is studying to be a nurse, posted the receipt on her Facebook account, along with the explanation: “This is what I got as a tip last night… so happy to live in the proud southern states...God Bless America, land of the free and home of the low class racists of Tennessee.”

The 19-year-old added: “They were extremely rude, but I introduced myself to them and they didn’t respond. When I came to take their order they simply told me they wanted their food and to put everything in a to-go box.”

Yet since the image went viral, some have suggested Jenkins added the insult herself because she was bitter she hadn’t received a tip.

Jenkins confirmed on Facebook she is now being “harassed” about the validity of the receipt but thanked her supporters, calling on them to continue sharing the image, because: "the more you share the more awareness we create."

Jenkins claims this racist slur was left for her by two of her customers on Saturday afternoon

It’s not the first time racial slurs have found their way onto food receipts.

Last year a Papa John’s pizza outlet was forced to apologise after a customer received a receipt identifying her as “lady chinky eyes”.

And in February 2012 a receipt purporting to show a banker leaving a 1% tip for a $133.54 bill and the ‘tip’ to “get a real job” went viral.